Add 20/42 and 70/18, Solve 20/42 + 3 16/18 as a fraction

Add 20/42 and 70/18

1^st number: 20/42, 2^nd number: 3 16/18

20/42 + 70/18 is 275/63.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 18 is 126

Next, find the equivalent fraction of both fractional numbers with denominator 126
For the 1st fraction, since 42 × 3 = 126,
20/42 = 20 × 3/42 × 3 = 60/126
Likewise, for the 2nd fraction, since 18 × 7 = 126,
70/18 = 70 × 7/18 × 7 = 490/126
Add the two like fractions:
60/126 + 490/126 = 60 + 490/126 = 550/126
550/126 simplified gives 275/63
So, 20/42 + 70/18 = 275/63
In mixed form: 423/63

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